This application claims the priority of German application 199 20 102.1, filed May 3, 1999, the disclosure of which is expressly incorporated by reference herein.
The present invention relates to a multi-chamber tube for a heat exchanger arrangement of a motor vehicle having at least two chamber sections. The chamber sections extend in parallel side-by-side, have widths which are significantly greater than their heights, and are used for different liquid or gaseous heat transfer media. The invention also relates to a heat exchanger arrangement for a motor vehicle having at least two heat exchangers and a common fin/tube block with a plurality of multi-chamber tubes as well as a plurality of fin arrangements.
European Patent Document EP 0 881 450 A1 relates to a heat exchanger arrangement for a motor vehicle which is known and which consists of two heat exchangers. The two heat exchangers have a common fin/tube block which is composed of a plurality of two chamber tubes as well as of a plurality of corrugated fins situated between the tubes. The two-chamber tubes are designed as extruded light-metal profiles and are provided with two chamber sections which extend in parallel to one another and which are each assigned to one heat exchanger. In one chamber section, several ducts which extend parallel to one another are additionally integrated. As a result of this heat exchanger arrangement, it is possible to provide common multi-chamber tubes as well as common corrugated fins for the two heat exchangers. This reduces the manufacturing expenditures required for the heat exchanger arrangement.
It is an object of the invention to provide a multi-chamber tube as well as a heat exchanger arrangement of the initially mentioned type which can be used in a simple manner for different liquid and gaseous heat transfer media.
This object is achieved in the multi-chamber tube by the provision of at least one chamber section with a greater height than that of at least one other chamber section. As a result, the multi-chamber tube is particularly suitable for a use in a heat exchanger arrangement which is constructed as a combination of a charge air cooler and a coolant radiator. The chamber section with the greater height has an enlarged flow-through volume so that suitable gaseous media can be used in a simple manner for heat transfer.
As a further development of the multi-chamber tube, this multi-chamber tube is shaped from a metal sheet which is plated by brazing on both sides. The multi-chamber tube, therefore, is produced by forming a sheet metal band or a thin-walled sheet metal bar, with opposed lateral edges of the sheet metal band or of the plate-shaped or strip-shaped sheet metal bar designed to rest against one another or on other wall sections of the sheet metal band or of the sheet metal bar. Desired tight connections are produced by a subsequent brazing-together operation in a brazing furnace or by a welding-together operation.
In a still further development of the invention, several ducts, which extend parallel to one another, are integrated in at least one chamber section. As a result of subdivision of the chamber section into several ducts, it becomes possible to guide a corresponding heat transfer medium through under an increased pressure. This chamber section, therefore, is particularly suitable for use in a condenser.
The object mentioned above is also achieved in a heat exchanger arrangement by providing a plurality of such multi-chamber tubes with at least one chamber section having a greater height than at least one other chamber section. The heat exchanger arrangement can be used particularly advantageously as a combination of a charge air cooler and a coolant radiator.
As a further development of the heat exchanger arrangement, each fin arrangement is formed by a one-piece combination of corrugated fin sections and web fin sections. The solid fin sections, which have a design which is basically known, are particularly advantageous for a charge air cooler. The one-piece design of the fin arrangements ensures secure cohesion of the fin/tube block of the heat exchanger arrangement.
As a further development of the invention, the multi-chamber tubes lead on the front side into a flow tank unit which has a common bottom, which is continuous over the width of the multi-chamber tubes, and which is provided with passages adapted to the different cross-sections of the chamber sections. This structure is particularly easy to produce. The flow tank unit, the fin arrangements, and the multi-chamber tubes are preferably produced from a light-metal alloy, so that the heat exchanger arrangement has an all-metal construction. The individual parts are advantageously preassembled to form a unit and are brazed together with one another in a single operation in a brazing furnace.
As yet a further development of the invention, an individual surrounding passage, which is correspondingly adapted in its width to the height of the chamber sections, is assigned to each multi-chamber tube. As a result, only a single operation per multi-chamber tube is required for producing the respective passage. The passages are designed such that, after brazing to the multi-chamber tubes, they have a tight connection so that the flow tank unit is tightly closed off in the bottom area.
As an even further development of the invention, the flow tank unit, including the bottom and the separating wall, is produced in one piece, by forming, from an individual metal sheet blank. As a result, a particularly simple production method is achieved for the flow tank unit.
Additional advantages and characteristics of the invention are reflected in the claims and will be apparent from the following description of preferred embodiments of the invention which are illustrated in the drawings.